A new generation of optoelectronic devices such as organic thin film transistors (OTFTs), organic light emitting transistors (OLETs), organic light emitting diodes (OLEDs), printable circuits, organic photovoltaic (OPV) devices, electrochemical capacitors, and sensors are built upon organic semiconductors as their active components. To enable high device efficiencies such as large charge carrier mobilities (μ) needed for transistor/circuit operations, or efficient exciton formation/splitting that is necessary for OLED/OPV operations, it is desirable that both p-type and n-type organic semiconductor materials are available. In addition, certain optoelectronic devices such as light emitting transistors require a semiconductor material which can transport both types of charge carriers efficiently. Furthermore, these organic semiconductor-based devices should exhibit satisfactory stability in ambient conditions and should be processable in a cost-effective manner. For example, a benchmark polymer, regioregular poly(3-hexylthiophene) (rr-P3HT), can provide hole mobilities ˜0.1 cm2/Vs and current modulation ≧105, close to amorphous silicon, but only under inert atmosphere.
Accordingly, the art desires new organic semiconductor materials, particularly those that can have good charge transport characteristics, processing properties, and stability in ambient conditions.